201Tl-99mTc subtraction scintigraphy in secondary hyperparathyroidism of chronic renal failure

In a group of 14 patients with chronic renal failure and secondary hyperparathyroidism, subtraction scintigraphy with 201Tl and 99mTc for parathyroid localisation was performed prior to subtotal parathyroidectomy. Fourteen of 38 (37%) enlarged hyperplastic glands found at first operation corresponded with the hot spots seen on the preoperative scans. Four of five (80%) found at a second operation had also been detected this way preoperatively. Postoperative scans were performed in nine patients. All hot foci seen on the preoperative scans had disappeared. In two patients new hot spots emerged correlating with known residual parathyroid tissue, and also in one patient with recurrent secondary hyperparathyroidism. We conclude that this diagnostic method is of limited value prior to the first neck exploration in secondary hyperparathyroidism of chronic renal failure. However it might be a useful method in the evaluation of patients with signs of persistent or recurrent hyperparathyroidism.